Method of detecting an analyte using a test element with nanofibers

Abstract

The invention concerns test elements, in particular diagnostic test elements, for determining the presence or concentration of biological, medical or biologically or medically effective substances including nucleic acids, proteins, viruses, microorganisms and cells, characterized in that these test elements contain nanofibers.

1. A method for qualitative or quantitative determination of an analyte in a bodily fluid sample, comprising:
 providing a test element having nanofibers comprising fleeces, fabrics, membranes, layers or combinations thereof, at least some of the nanofibers having a length of at least 2 mm and containing more than one polymer bead thereon; 
 providing a photometric or electrochemical detection reagent with the test element for detecting the analyte in the bodily fluid sample; 
 applying the bodily fluid sample to the test element, wherein the nanofibers act on the liquid sample; and 
 determining a quantitative or qualitative property of the bodily fluid sample. 
 
     
     
       2. The method of  claim 1 , wherein the bodily fluid sample comprises blood and the nanofibers act as a filter to separate red blood cells from the bodily fluid sample. 
     
     
       3. The method of  claim 1  wherein the nanofibers have a diameter of 10 to 2000 nm. 
     
     
       4. The method of  claim 1  wherein the nanofibers have a diameter of 10 to 1000 nm. 
     
     
       5. The method of  claim 1  wherein the nanofibers have a diameter of 10 to 500 nm. 
     
     
       6. The method of  claim 1  wherein the nanofibers are hydrophilic nanofibers. 
     
     
       7. The method of  claim 1  wherein the nanofibers are hydrophobic nanofibers. 
     
     
       8. The method of  claim 1  wherein the nanofibers include both hydrophilic and hydrophobic nanofibers. 
     
     
       9. The method of  claim 1  wherein the step of providing a test element comprises providing a hydrophobic non-porous support material and applying the nanofibers to the support material, the nanofibers being hydrophilic nanofibers. 
     
     
       10. The method of  claim 1  wherein the step of providing a test element comprises providing a support material having a plurality of test fields and applying the nanofibers to the support material between the plurality of test fields, the nanofibers being hydrophobic nanofibers. 
     
     
       11. The method of  claim 1  wherein the step of providing a test element comprises providing a support material and applying hydrophilic nanofibers to the support material to define a plurality of test fields and applying hydrophobic nanofibers to the support material between the plurality of test fields. 
     
     
       12. The method of  claim 1  wherein the step of providing a test element comprises providing a support material and applying the nanofibers to the support material by electrospinning a hydrophobic base material onto the support material. 
     
     
       13. The method of  claim 12  wherein the nanofibers formed by electrospinning a hydrophobic base material form a super hydrophobic surface. 
     
     
       14. The method of  claim 13  wherein the nanofibers forming a super hydrophobic surface form a layer with a thickness of no more than about 2 μm on the support material. 
     
     
       15. The method of  claim 1  wherein the step of providing a test element comprises providing a support material and applying the nanofibers on the support material wherein the nanofibers are a mixture of hydrophilic and hydrophobic nanofibers and form a thin layer on the support material. 
     
     
       16. The method of  claim 15  further comprising the step of applying the photometric or electrochemical detection reagent in liquid form to the thin layer of nanofibers. 
     
     
       17. The method of  claim 16  wherein the photometric or electrochemical detection reagent is applied at a mass per unit area of 10 to 500 mg/m 2 . 
     
     
       18. The method of  claim 1  wherein the nanofibers are composed of polymers selected from polyolefins, polyaromatic compounds, fluorinated or partially fluorinated polymers, polyesters, polyamides, polyurethanes, polyvinyl alcohols, polyvinyl amines, polyethyleneimines, polyalkylene oxides and combinations and copolymers thereof. 
     
     
       19. The method of  claim 1  wherein the nanofibers form a filter element and wherein the step of applying the bodily fluid sample to the test element includes filtering the bodily fluid sample with the nanofibers. 
     
     
       20. The method of  claim 19  wherein filtering the bodily fluid sample with the nanofibers includes separating blood cells from the bodily fluid sample. 
     
     
       21. The method of  claim 1  wherein the nanofibers form a fleece. 
     
     
       22. The method of  claim 21  wherein the fleece has a thickness of 0.02 μm to 50 μm. 
     
     
       23. The method of  claim 21  wherein the fleece has a thickness of 0.08 μm to 2 μm. 
     
     
       24. The method of  claim 1  wherein the nanofibers form a thin layer having a mass per unit area of 10 to 50 mg/m 2 . 
     
     
       25. The method of  claim 1  wherein the nanofibers form an asymmetric membrane.